EXT4-fs (loop2): unmounting filesystem 00000000-0000-0000-0000-000000000000.
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BUG: KCSAN: data-race in data_push_tail / uuid_string

write to 0xffffffff86ec8a59 of 1 bytes by task 3090 on cpu 1:
 string_nocheck lib/vsprintf.c:649 [inline]
 uuid_string+0x435/0x4b0 lib/vsprintf.c:1730
 pointer+0x3ee/0xd10 lib/vsprintf.c:2447
 vsnprintf+0x861/0xe20 lib/vsprintf.c:2822
 va_format lib/vsprintf.c:1682 [inline]
 pointer+0x8a1/0xd10 lib/vsprintf.c:2449
 vsnprintf+0x861/0xe20 lib/vsprintf.c:2822
 vscnprintf+0x42/0x80 lib/vsprintf.c:2924
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2130
 vprintk_store+0x56f/0x800 kernel/printk/printk.c:2244
 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2290
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2324
 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2334
 __ext4_msg+0x18a/0x1a0 fs/ext4/super.c:998
 ext4_put_super+0x91/0x7d0 fs/ext4/super.c:1303
 generic_shutdown_super+0xdb/0x210 fs/super.c:693
 kill_block_super+0x2a/0x60 fs/super.c:1646
 ext4_kill_sb+0x44/0x80 fs/ext4/super.c:7305
 deactivate_locked_super+0x73/0x1c0 fs/super.c:481
 deactivate_super+0x9b/0xb0 fs/super.c:514
 cleanup_mnt+0x272/0x2e0 fs/namespace.c:1254
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1261
 task_work_run+0x135/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd1/0xe0 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:296
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffffffff86ec8a58 of 8 bytes by task 3105 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:590 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:675
 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1046
 prb_reserve+0x893/0xbc0 kernel/printk/printk_ringbuffer.c:1555
 vprintk_store+0x53e/0x800 kernel/printk/printk.c:2234
 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2290
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2324
 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2334
 __ext4_msg+0x18a/0x1a0 fs/ext4/super.c:998
 ext4_put_super+0x91/0x7d0 fs/ext4/super.c:1303
 generic_shutdown_super+0xdb/0x210 fs/super.c:693
 kill_block_super+0x2a/0x60 fs/super.c:1646
 ext4_kill_sb+0x44/0x80 fs/ext4/super.c:7305
 deactivate_locked_super+0x73/0x1c0 fs/super.c:481
 deactivate_super+0x9b/0xb0 fs/super.c:514
 cleanup_mnt+0x272/0x2e0 fs/namespace.c:1254
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1261
 task_work_run+0x135/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd1/0xe0 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:296
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x000000010001c807 -> 0x2d30303030303030

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3105 Comm: syz-executor.2 Not tainted 6.5.0-syzkaller-11812-g7733171926cc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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